从猪肾和大鼠肾中分离出的肾素的性质比较。

A comparison of the properties of renin isolated from pig and rat kidney.

作者信息

Lauritzen M, Damsgaard J J, Rubin I, Lauritzen E

出版信息

Biochem J. 1976 May 1;155(2):317-23. doi: 10.1042/bj1550317.

DOI:10.1042/bj1550317

PMID:938482

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1172837/

Abstract

On isoelectric focusing, renin from rat kidneys showed three activity peaks with pI values at pH 5.0, 5.2 and 5.4 after a purification procedure involving differential centrifugation, acidification, chromatography on Sephadex G-75 and dialysis. 2. The preparation (purified 140-fold) was compared with a crude kidney extract in the absence and presence of 3 M-urea by isoelectric focusing. The pattern of activity distribution was confirmed by these experiments and the content of isoenzymes in the three groups calculated. 3. Pig renin was prepared and compared with rat renin with regard to molecular weight, acid activation, behaviour on isoelectric focusing, immunogenicity and substrate affinity. 4. Extracts of rat kidney contained multiple forms of renin with mol.wt. between 39000and 42000, whereas active pig renin had an approximate mol.wt. of 40000. Acidification of rat renal extracts did not increase the activity of renin, indicating the absence of an inactive form of renin in rat kidneys, whereas pig renin was activated by this procedure. Pig renin has isoelectric points at pH 4.6, 4.8, 5.05 and 5.2, significantly lower than for rat renin. The isoenzymes from the two species had no antigenicity in common, as shown by crossed immunoelectrophoresis or rocket immunoelectrophoresis. 5. The Michaelis constants for pig and rat renin were in the same range, 1 X 10(-6) M, when rat renin substrate was used. The relative content of rat isoenzyme with pI in the pH ranges 4.9-5.1, 5.1-5.3 and 5.3-5.5 was approx. 20, 27 and 53% respectively. Purified pig renin prepared in two different ways had isoenzymes with pI in the pH regions 4.5-4.7, 4.7-4.9, 4.9-5.05 and 5.05-5.20 in the approximate proportions 14, 24, 28 and 29%.

摘要

在等电聚焦过程中，经过差速离心、酸化、葡聚糖凝胶G - 75柱层析和透析的纯化步骤后，大鼠肾脏中的肾素在pH 5.0、5.2和5.4处显示出三个活性峰，其等电点（pI）值分别在此处。2. 通过等电聚焦，将该制剂（纯化了140倍）与粗制肾脏提取物在有无3M尿素的情况下进行比较。这些实验证实了活性分布模式，并计算了三组中同工酶的含量。3. 制备了猪肾素，并在分子量、酸激活、等电聚焦行为、免疫原性和底物亲和力方面与大鼠肾素进行了比较。4. 大鼠肾脏提取物含有多种形式的肾素，分子量在39000至42000之间，而活性猪肾素的近似分子量为40000。大鼠肾脏提取物的酸化并未增加肾素的活性，表明大鼠肾脏中不存在无活性形式的肾素，而猪肾素可通过此步骤被激活。猪肾素的等电点在pH 4.6、4.8、5.05和5.2处，明显低于大鼠肾素。如交叉免疫电泳或火箭免疫电泳所示，来自这两个物种的同工酶没有共同的抗原性。5. 当使用大鼠肾素底物时，猪和大鼠肾素的米氏常数在相同范围内，为1×10⁻⁶M。大鼠等电点在pH范围4.9 - 5.1、5.1 - 5.3和5.3 - 5.5的同工酶相对含量分别约为20%、27%和53%。以两种不同方法制备的纯化猪肾素，其同工酶的等电点在pH区域4.5 - 4.7、4.7 - 4.9、4.9 - 5.05和5.05 - 5.20，比例约为14%、24%、28%和29%。